I completely agree that the deck resistance doesn't change. Where we are missing each other is understanding how the mod works. That black line is not some mythical thing I imagined. That represents the values the mod is calculating as the target values it needs to hit at given temperatures. The mod itself is treating the whole coil+deck as a single system, but it doesn't know that only part of that system is variable (the coil) and part (the deck) is constant. The mod just takes the base reading of 0.245 and uses the TCR to generate that black line. And that black line is wrong. Sorry to be stubborn about this, but honestly can you tell me where in my step-by-step of what's going on I missed something? I'll post it again here: Mod reads starting ohm of 0.245 (0.18 from coil, 0.065 from deck) I set my mod to a temp of 392F Mod uses TCR to calculate target resistance of 0.305858 (0.245 X 1.2484) Mod applies power until resistance reaches 0.305858 If anything else is happening, please tell me. Again, I'm open to being proven wrong, I just need to know exactly where I went off the rails.